Experimental Channel Statistics of Drone-to-Ground Retro-Reflected FSO Links With Fine-Tracking Systems. - Phuc V. Trinh; Alberto Carrasco-Casado; Takuya Okura; Hiroyuki Tsuji; Dimitar R. Kolev; Koichi Shiratama; Yasushi Munemasa; Morio Toyoshima (IEEE Access, 2021)